The use of arrays of electro-acoustic transducers deployed from sonobuoys has a variety of applications in military and commercial fields. A commercial application Consists of using such an array to receive reflected acoustic waves in oil exploration surveys. Submarine detection is the principle use in the military field. While individual sonobuoys having a single transducer or a vertical line array of transducers are useful for some applications, other applications require the use of an array of multiple transducers arranged in a horizontal line at a predetermined depth below the water's surface, sometimes extending over a substantial distance.
Typically, such horizontal array systems comprise a horizontal line array, consisting of a cable having a plurality of transducers mounted thereon at a selected interval, and vertical suspension cables, attached to the leading and trailing ends of the horizontal array cable and including selected motion isolation and drag inducing components. In the prior art, such systems have been deployed sequentially. That is, first the trailing end vertical suspension cable is paid out from the deploying sonobuoy, followed by the array cable, and finally the leading end vertical suspension cable. The system then is allowed to stabilize, with the leading and trailing end suspension cables in a vertical attitude and the array in a horizontal attitude.
While the above described deployment method is satisfactory for some applications, other applications require that the transducer array be deployed very rapidly or at a shallow depth. But, the time required for deployment is a function of the length of the horizontal array and the length of the suspension cables, the latter of which also determines the depth at which the array will be deployed. For example, a deployment time of thirty minutes is desirable for some applications. However, due to the length of the array involved and the time required for the array to reach the desired operating depth, the prior art sequential method of deployment has been unable to achieve the desired thirty-minute deployment time.
It is, therefore, an object of the present invention to provide a new and improved system for rapidly deploying a horizontal line array of electroacoustic transducers from a sonobuoy, as well as new sonobuoys employing such system.